After initially believing Hughes would miss six to eight weeks, the Bulls now believe the veteran guard will be sidelined just two to four weeks.
His absence will mean Hughes will miss anywhere from five to 12 games. Chicago opens the regular season Tuesday at home against the Milwaukee Bucks.
Hughes left the Bulls' preseason game against Minnesota on Wednesday with 3:16 to play in the third quarter and did not return after getting his arm caught under Wolves forward Mike Miller as the two dove for a loose ball. Hughes was leading Chicago with 21 points when he left.